B Question on Schwarzschild Geometry

AI Thread Summary
The discussion centers on the relationship between mass, Schwarzschild radius, and density in celestial bodies. A specific equation is proposed to calculate mass based on the Schwarzschild radius and a defined volume, but there are significant issues with unit consistency. The participants highlight that mass cannot be derived from a radius multiplied by volume due to dimensional discrepancies. The constant derived from the Schwarzschild radius is clarified to represent a fixed mass per centimeter of radius. Overall, the conversation emphasizes the importance of proper unit application in astrophysical calculations.
nabil23
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please interpret this observation. There is a specific radius through a given equation that always gives the correct mass to any star or planet, as well a density. What is the logical explanation for this?
Mass = (4π/3) x schwarzschild radius of the star x 4π/3 x (726696460.5 cm.) cube.
For example Earth mass is equal to:

M= 4.188786667 x 0.8870085587 cm. x 4.188786667 x (726696460.5 cm.) cube = 5.9726 x (10) +27 gram.

(4π/3) = 4.188786667
schwarzschild radius of the Earth = 0.8870085587 cm.
the mentioned radius = 726696460.5 cm.
the density of Earth is equal to:
earth density ρ= M/V = (4π/3) x 0.8870085587 cm. x (4π/3) x (726696460.5 cm) cube /(4π/3) x (637758965.3 cm) cube = Earth density.
the radius of the Earth = 637758965.3 cm.
thank you for your contribution and your effort in providing explanation.
 
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The Schwarzschild radius is the mass multiplied by a constant. You've divided by that constant (or multiplied by its reciprocal). Unsurprisingly, the result is the mass.

Edit: Well, numerically at least. Your units are messed up - a radius times a volume is not a mass.
 
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I think that schwarzschild radius is equal to:
schwarzschild radius = M/(C x C/2G) = M/6.733418682 x (10) +27
any mass divided on schwarzschild radius will give this constant:
M/schwarzschild radius = 6.733418682 x (10) +27
this constant is actually equal to :
(4π/3) x (4π/3) x (726696460.5 cm.) cube = 6.733418682 x (10) +27
c= 29979245800 cm. speed of light in centimeter/second.
726696460.5 is the mentioned radius mentioned above.
 
You've still got messed up units. ##G/c^2## has dimensions of ##LM^{-1}## (units of cm/kg, in the system you are using). This cannot be meaningfully equal to a radius cubed. It's like saying I weigh 70 miles per hour. It's nonsense - I weigh 70kg. The numbers are the same but the meaning is totally different.
 
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you are absolutely right :
Mass/ schwarzschild radius = M/rs = c x c/2G = ML-1 = 6.733418682 x (10) +27 gram/centimeter
it means 6.733418682 x (10)+27 gram for every 1 centimeter of schwarzschild radius length.
 
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